Electrically-generated steam-vulcanizer.



i be observed that the spring in my invention ture falls below thedesired limit, whereupon the current again passes between the cont-actpoints 84 and 35.

It is desirable that the current used in the vulcanizer be alternating,for the reason that with a direct current too great an` arc is formedbetween the contact points 34 and 35. It. is for this purpose that I usethe condenser 36, which prevents the formation of the arc when a directcurrent is used.

It will be seen that the apparatus herein -disclosed is very economicaland etlicient,

because the electric heater is entirely surrounded by water. LThe meansfor maintaining the 4temperature of the vulcanizer uniform is veryaccurate, since the slightest excess over the desired pressure 'breaksthe electric circuit and prevents the further del velopmentof heat,until the temperature has again been reduced to the'predeterminedVdegree. Moreover, the device is no topen to the objection heretoforefoundfto exist in'` vulcanizers which depend upon a spring fortransmitting pressure, as: such springs bef come imperfect in theiroperation by the re-v peated action of the Ysteam therein. It is to isnot exposed to the action of the steam. At the same time it can -beeasily adjusted to give accurate results.

By reason of a slightwelding that may occur between-the two pointsofcontactit 50 times as great as that of the end of the rod. It isnecessary that' its movement should belarge in order to obtain-accuratereadings. Prior devices have been employed in which the movement of thepointer itself Vhas been utilized to break the electric circuit.

From what hasbeen already stated it will readily be seen that suchdevices are imperfect, because the amplitude of movement of the pointermust be very great, and therefore the force applied at the end of thefpointer must be proportionately small, and this force has not been foundsufficient to be -depended upon to break the circuit at all times.

I"claim: A vulcanizer comprising a hollow casing,

an electric heater therein, a diaphragml adapted to receive on one sidethe pressure of steam generated by said-heater from water in saidcasing, a rod moved by the movement of the diaphragm under theinlfluence .of said pressure, a circuit breaker in the circuit oftheelectric heater, a movable p inter and means coperating vtherewith foril dicating the pressure, said rod being arranged by its movement due tothe increase of steam pressure to operate said circuit breaker to breakthe circuit, and a positive train of mechanism connecting said rod withsaid pointer to positively move said pointer correspondingly with themovement of said rod, the movement of the end of the pointer produced bysaid rod being many times .greater than that of the movement `of thecontact breaker produced thereby. In testimony whereof I have hereuntoset my hand in the presence'of two subscribing witnesses.l y ANSEL C.HULBERT.

Witnesses:

FRANCIS M. WRIGHT, D. B. RICHARDS.-

